Why is my mesh flipping? (Rigid body simulation)
I had the same problem in blender 3.0, the cause was the object having a negative scale. It worked fine after updating the object's scale with positive values.
This link posted in one of the previous answers was useful:

https://blenderartists.org/forum/showthread.php?311350-Rigid-Body-Tools-turns-my-object-upside-down.